Research and Scientific Proof
It's been said that herbal medicines and pharmaceuticals arrive at the same destination — the shelf in your neighborhood drug store — from opposite directions. Pharmaceuticals are created in a lab in response to a specific need or to treat a specific condition. Herbs have been around for ages while humans have proceeded, through trial and error, to figure out how to use them.
Preclinical research involves basic science and usually begins with in vitro studies, which are conducted on isolated cells (in vitro means “within the glass” in Latin). In vitro studies gauge a substance's effects on live tissue.
According to the World Health Organization, ninety-two countries around the world have a system of national regulation for herbal medicines. The United States is one of only a handful of industrialized nations to have no policy. Nearly all countries allow herbals to be sold as OTC drugs, and about half allow herbal medicines to be sold as prescription medicines.
Next, in vivo (or “within the living”) research uses live animals, often mice and rats, to see what the substance does to a living animal.
Human studies, as you might expect, are experiments conducted on people. They can involve epidemiological research, which analyzes data on the use of the herb in a particular group and its relationship to disease and mortality rates, or an analysis of several previously published human trials (called a meta-analysis).
Human research also involves clinical trials, which compare the substance to a drug or other agent or to a placebo, which is a substance with no pharmaceutical effect (a “sugar pill”), to determine its effectiveness. The best trials are double-blind, meaning that neither the subjects nor the test administrators know who is getting the herb and who is getting the other agent or placebo. This eliminates the risk of prejudice.
Because they must go through a much more elaborate process in order to be approved for sale, pharmaceuticals are much more rigorously tested than herbs (remember, it's much easier to get “dietary supplement” than “drug” status). Thus, the research on many herbs stops at the in vivo stage.
However, there have been several important human clinical trials on herbs in recent years, many of which have shown herbs to be safe and effective alternatives to synthetic drugs.
Other Kinds of Evidence
Of course, herbs do have one big advantage over drugs: They've been used safely and successfully for thousands of years. Dose for dose, they are almost always less potent than their pharmaceutical counterparts, meaning they present far less risk of toxicity than drugs do. Many have no known side effects (or very, very mild ones) for people who are otherwise healthy and not taking other medications. Nonetheless, they are medicines and should be treated with care.
Some herbs can interact with cytochrome P450 (CYP), a group of enzymes that are involved in the metabolism of several drugs. There are CYP enzymes that are known to have drug or herb interactions. Be sure to talk with your doctor if you're taking any medications long term, as they might be on the CYP “potential interactions” list.